The fourth edition of Webster's New World College Dictionary defines "phobia" as an "irrational, excessive and persistent fear of some particular thing or situation."
The Diagnostic and Statistical Manual of the American Psychiatric Association takes that definition a step further, adding one, more serious, requirement. "We're not supposed to make a diagnosis of a phobia if it doesn't affect a person's life," said Dr. P.V. Nickell, chairman of psychiatry at Allegheny General Hospital and interim chairman of psychiatry at the Western Pennsylvania Hospital Forbes Regional Campus.
"If a corn farmer in the Midwest is afraid of close spaces, you wouldn't diagnose it as a phobia because it doesn't affect him.
"On the other hand, if someone wants to be a deep miner in Western Pennsylvania and is afraid of close spaces, you would diagnose it because it would prevent him or her from doing the job."
And so it was for a patient of Dr. Robert Hudak, assistant professor of psychiatry at the University of Pittsburgh and director of the Obsessive-Compulsive Disorders Clinic at Western Psychiatric Institute & Clinic of UPMC.
"There was a woman who was in her mid-20s -- call her 25 years old -- who had recently graduated from college and had a job with a business that was involved in flying to different companies," Dr. Hudak said.
"They contracted out to other companies all over the country, so the job involved getting on an airplane and going across the United States."
The woman liked the job and the people with whom she worked and she also was making "very good money."
There was just one problem: She was afraid of flying.
"She managed to avoid it the first couple months," he said. "She avoided it by saying things like, 'I'm new, I need to settle in.' It worked out fine [for a while], but she was dreading getting on a plane."
Finally she couldn't avoid an assignment that involved flying any longer.
"She had to tell [her supervisors] 'I don't really want to fly. I'm too afraid.' The boss actually had to fire her.
"She wasn't real interested in treatment [at that time]," Dr. Hudak added. "Her fear was so great it was easier to get fired and look for another job."
Much later, she began seeing Dr. Hudak and after that she saw a therapist as well.
"The last I heard she was flying occasionally," he said.
Patients with phobias like hers are said to have "specific phobias." This category of phobias includes irrational, life-altering fears of single things like dogs, snakes, blood, needles, or thunder and lightning.
The other categories are agoraphobia, which is essentially always associated with a panic disorder, and social phobias.
Translated from the Greek, agoraphobia literally means fear of the market place, "so what that means is [people] have spontaneous panic attacks and they start attributing the cause of the panic attack to the situation in which they are when the attack occurs, so they start avoiding the situation," Dr. Nickell said.
"[Eventually] they start staying at home to avoid having a panic attack."
That part of the disorder is the phobia aspect, but Dr. Hudak said he's "not sure that can be considered a true phobia or not."
But a social phobia "is an entity on its own," he said.
"It's stage fright [multiplied] times 10 or 20," Dr. Nickell said. "There are different subtypes of social phobias. The most common is public speaking and while most people may have some anxiety speaking in public, social phobics can't, or become so anxious they mumble, or they're unintelligible, or they don't remember what they said."
There are other subtypes of social phobias, with two common ones being fear of eating in public and fear of public restrooms.
Dr. Nickell has a female middle-aged patient with a professional support job whose specific social phobia was talking on the telephone.
"That really caused her some significant difficulties in her work," Dr. Nickell said, "and so basically she was working below her level of skill and ability to avoid having to routinely answer the phone. ... For her [it was] a fear of how people would judge her by her telephone manners. Of course, when she worried, she stumbled on words and [her fear] was self-fulfilling."
Dr. Nickell prescribed two psychotropic drugs, and she did talk therapy with a psychologist.
"She's better. It's not completely better," Dr. Nickell said. "She took a job that more fits her skills and abilities." And, he said, she uses the phone.
Specific phobias, which are what most laypeople are referring to when they speak of phobias, fall into four types: animal, blood injection injury like getting shots or giving blood, environmental like heights or water, and situational, like being in a close space.
Asked how many of them there are, both Drs. Nickell and Hudak were, for several reasons, unable to answer.
"I suppose there's a finite number, but it's huge. There are common ones and then uncommon ones. I've never seen a number [printed anywhere]," Dr. Nickell said.
"A phobia can be virtually about anything," Dr. Hudak said. "Our concern is how the patient reacts to the phobia rather than to what the actual phobia is, so knowing what the phobia is, is important only in designing a person's individual treatment."
Besides, people with phobias usually don't seek psychiatric help, the two doctors said.
"Some simply avoid the situation that may trigger the phobias," Dr. Hudak said. "Most of those people don't present themselves for treatment because if you can avoid it you don't need to come in and see anybody."
Also, he said, people might think their phobias are silly "and people around them say ... 'Get over it.' " That doesn't motivate them to seek treatment.
Dr. Nickell said, "Most people realize they have phobias when they see me for something else, not because they came in to have it treated. I treat it if it causes specific difficulties. Most people have figured out ways to deal with phobias so they don't cause huge problems day in and day out."
The two doctors differ slightly on the cause of phobias.
"I'm not sure anyone really knows," Dr. Nickell said. "They don't seem to be biologically driven like schizophrenia is, for example. But they don't seem to be psychodynamic either. The reason I made the last comment [is] sometimes you have a bad experience, as like a child with a dog who then has a dog phobia. But most people can't track [a phobia] to a specific problem."
However, Dr. Hudak thinks genes are involved.
"People have a genetic vulnerability, a kind of biological vulnerability to a phobia and then interaction between the person's biology and the environment [causes the phobia]," he said.
Can they be cured?
"They can be treated," Dr. Hudak said. "I like the word 'treated' rather than 'cured.' "
One type of treatment is called "desensitization." It is, for example, sometimes used to treat people with phobias about flying.
"It's exposing them to all aspects of flying," Dr. Hudak said. "They visit the airport. Then they go inside the airplane. Then they may take them on a flight." The person with the phobia also might be encouraged to imagine himself flying.
"It requires work," Dr. Nickell said. "Medicines typically don't help specific phobias. Certain different types of psychotherapy can be helpful, but they're a lot of work. Theoretically, any phobia can be cured or reduced to where it doesn't significantly negatively impact a person."